Risk
4/6/2010
04:30 PM
50%
50%

Researcher Details New Class Of Cross-Site Scripting Attack

'Meta-Information XSS' exploits commonly used network administration utilities

A new type of cross-site scripting (XSS) attack that exploits commonly used network administration tools could be putting users' data at risk, a researcher says.

Tyler Reguly, lead security research engineer at nCircle, today published a white paper outlining a new category of attack called "meta-information XSS" (miXSS), which works differently than other forms of the popular attack method -- and could be difficult to detect.

"Think about those network administration utilities that so many webmasters and SMB administrators rely on -- tools that perform a whois lookup, resolve DNS records, or simply query the headers of a Web server," the white paper states. "They're taking the meta-information provided by various services and displaying it within the rendered Website.

"These Web-based services introduce a class of XSS that can't be captured by the current categories."

Reguly explains that there are three current types of XSS attacks: reflected, persistent, and DOM-based.

"Reflected XSS refers to an attack that occurs when user input is reflected back at the user," he writes. "This means that you provide the malicious data as user input, and the Web application simply echoes the data back to you.

"Persistent XSS refers to an attack that stores user input, allowing it to affect a much broader scope of visitors. An attack may be stored in the database and displayed to all visitors, rather than just the visitor that provided the malicious input."

DOM-based XSS refers to attacks that modify the Document Object Model directly and don't require data in the HTTP response, Reguly says.

"None of these [categories] really captures the process that occurs when you are dealing with [miXSS]," the paper says. "With miXSS, the input that the user provides is completely valid and properly sanitized. This rules out reflected XSS, and since we aren't storing the user input, persistent XSS can also be disregarded. Finally, since we're not interacting with the DOM, we can eliminate this type of attack."

MiXSS has aspects of both reflected and persistent attacks, but does not fall into either category, Reguly explains. "It is valid user input provided to a service," he says. "The service then utilizes the user-provided data to gather data and display it for the user. It is in this data that the cross-site scripting occurs." Reguly offers an example: a DNS TXT record that contains [a certain value] and a service designed to gather DNS TXT records for the purpose of testing sender policy framework (SPF) records.

"The user provides the domain name pointing to the TXT record, while the service resolves the TXT data and displays the data to the user," the paper says. "Since the data contains JavaScript, the returned data is processed, and successful cross-site scripting has occurred."

The XSS vulnerability could be a growing threat in the future, Reguly says, because Web-based tools such as these are increasingly used to quickly resolve network administration issues that might otherwise inhibit the user experience, the paper says.

Have a comment on this story? Please click "Discuss" below. If you'd like to contact Dark Reading's editors directly, send us a message.

Tim Wilson is Editor in Chief and co-founder of Dark Reading.com, UBM Tech's online community for information security professionals. He is responsible for managing the site, assigning and editing content, and writing breaking news stories. Wilson has been recognized as one ... View Full Bio

Comment  | 
Print  | 
More Insights
Register for Dark Reading Newsletters
White Papers
Cartoon
Current Issue
Dark Reading Tech Digest, Dec. 19, 2014
Software-defined networking can be a net plus for security. The key: Work with the network team to implement gradually, test as you go, and take the opportunity to overhaul your security strategy.
Flash Poll
Video
Slideshows
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2014-8142
Published: 2014-12-20
Use-after-free vulnerability in the process_nested_data function in ext/standard/var_unserializer.re in PHP before 5.4.36, 5.5.x before 5.5.20, and 5.6.x before 5.6.4 allows remote attackers to execute arbitrary code via a crafted unserialize call that leverages improper handling of duplicate keys w...

CVE-2013-4440
Published: 2014-12-19
Password Generator (aka Pwgen) before 2.07 generates weak non-tty passwords, which makes it easier for context-dependent attackers to guess the password via a brute-force attack.

CVE-2013-4442
Published: 2014-12-19
Password Generator (aka Pwgen) before 2.07 uses weak pseudo generated numbers when /dev/urandom is unavailable, which makes it easier for context-dependent attackers to guess the numbers.

CVE-2013-7401
Published: 2014-12-19
The parse_request function in request.c in c-icap 0.2.x allows remote attackers to cause a denial of service (crash) via a URI without a " " or "?" character in an ICAP request, as demonstrated by use of the OPTIONS method.

CVE-2014-2026
Published: 2014-12-19
Cross-site scripting (XSS) vulnerability in the search functionality in United Planet Intrexx Professional before 5.2 Online Update 0905 and 6.x before 6.0 Online Update 10 allows remote attackers to inject arbitrary web script or HTML via the request parameter.

Best of the Web
Dark Reading Radio
Archived Dark Reading Radio
Join us Wednesday, Dec. 17 at 1 p.m. Eastern Time to hear what employers are really looking for in a chief information security officer -- it may not be what you think.